501 research outputs found

    'I am not a depressed person': how identity conflict affects help-seeking rates for major depressive disorder.

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    This is the final version of the article. Available from the publisher via the DOI in this record.BACKGROUND: There is a significant treatment gap for patients with depression. A third of sufferers never seek help, and the vast majority of those who do only do so after considerable delay. Little is understood regarding poor help-seeking rates amongst people with depression, with existing research mainly focussed on the impact of barriers to treatment. The current study explored psychological factors affecting help-seeking behaviour in clinically depressed individuals. METHODS: Semi-structured interviews were conducted with 20 current or previously clinically depressed participants who either had or had not sought professional help. Thematic analysis was used to analyse results. RESULTS: The onset of depressive symptoms created conflict with participants' identity and personal goals. Delays in seeking help were primarily attributed to the desire to protect identity and goals from the threat of depressive symptoms. Participants used avoidance strategies to reduce the perceived threat of depressive symptoms on identity. These strategies interfered with help-seeking. Help-seeking was only undertaken once participants reached a point of acceptance and began to make concessions in their identity and goals, at which time they reduced their use of avoidance. CONCLUSIONS: Difficulties resolving conflict between identity and depressive symptoms may account for significant delays in seeking help for depression. The results have implications for predicting health behaviour and improving treatment uptake for depression, and may inform existing help-seeking models

    Mineralogic variations in fluvial sediments contaminated by mine tailings as determined from AVIRIS data, Coeur D'Alene River Valley, Idaho

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    The success of imaging spectrometry in mineralogic mapping of natural terrains indicates that the technology can also be used to assess the environmental impact of human activities in certain instances. Specifically, this paper describes an investigation into the use of data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) for mapping the spread of, and assessing changes in, the mineralogic character of tailings from a major silver and base metal mining district. The area under investigation is the Coeur d'Alene River Valley in northern Idaho. Mining has been going on in and around the towns of Kellogg and Wallace, Idaho since the 1880's. In the Kellogg-Smelterville Flats area, west of Kellogg, mine tailings were piled alongside the South Fork of the Coeur d'Alene River. Until the construction of tailings ponds in 1968 much of these waste materials were washed directly into the South Fork. The Kellogg-Smelterville area was declared an Environmental Protection Agency (EPA) Superfund site in 1983 and remediation efforts are currently underway. Recent studies have demonstrated that sediments in the Coeur d'Alene River and in the northern part of Lake Coeur d'Alene, into which the river flows, are highly enriched in Ag, Cu, Pb, Zn, Cd, Hg, As, and Sb. These trace metals have become aggregated in iron oxide and oxyhydroxide minerals and/or mineraloids. Reflectance spectra of iron-rich tailing materials are shown. Also shown are spectra of hematite and goethite. The broad bandwidth and long band center (near 1 micron) of the Fe(3+) crystal-field band of the iron-rich sediment samples combined with the lack of features on the Fe(3+) -O(2-) charge transfer absorption edge indicates that the ferric oxide and/or oxyhydroxide in these sediments is poorly crystalline to amorphous in character. Similar features are seen in poorly crystalline basaltic weathering products (e.g., palagonites). The problem of mapping and analyzing the downriver occurrences of iron rich tailings in the Coeur d'Alene (CDA) River Valley using remotely sensed data is complicated by the full vegetation cover present in the area. Because exposures of rock and soil were sparse, the data processing techniques used in this study were sensitive to detecting materials at subpixel scales. The methods used included spectral mixture analysis and a constrained energy minimization technique

    Discrimination of poorly exposed lithologies in AVIRIS data

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    One of the advantages afforded by imaging spectrometers such as AVIRIS is the capability to detect target materials at a sub-pixel scale. This paper presents several examples of the identification of poorly exposed geologic materials - materials which are either subpixel in scale or which, while having some surface expression over several pixels, are partially covered by vegetation or other materials. Sabol et al. (1992) noted that a primary factor in the ability to distinguish sub-pixel targets is the spectral contrast between the target and its surroundings. In most cases, this contrast is best expressed as an absorption feature or features present in the target but absent in the surroundings. Under such circumstances, techniques such as band depth mapping (Clark et al., 1992) are feasible. However, the only difference between a target material and its surroundings is often expressed solely in the continuum. We define the 'continuum' as the reflectance or radiance spanning spectral space between spectral features. Differences in continuum slope and shape can only be determined by reduction techniques which considers the entire spectral range; i.e., techniques such as spectral mixture analysis (Adams et al., 1989) and recently developed techniques which utilize an orthogonal subspace projection operator (Harsanyi, 1993). Two of the three examples considered herein deal with cases where the target material differs from its surroundings only by such a subtle continuum change

    Rock spectral classes observed by the Spirit Rover’s Pancam on the Gusev Crater Plains and in the Columbia Hills

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    This paper examines the ferrous and ferric iron mineralogy of rocks inferred from 246 visible/near-infrared (430–1010 nm) multispectral observations made by the Mars Exploration Rover Spirit’s Pancam on its traverse from its landing site to its second Winter Haven location. Principal component, correspondence analyses, and a sequential maximum angle convex cone technique were used to identify 14 candidate classes. Spectra from the West Spur of Husband Hill and the Watchtower area had the highest 535 and 601 nm band depths indicating that these areas were more oxidized. Differences in the depth and band center of a near infrared (NIR) absorption feature were observed using 904 nm band depth and 803:904 nm ratio and parameters gauging the 754–864 and 754–1009 nm slopes. Spectra of rocks from the southern flank of Husband Hill had negative 754–1009 nm slopes and a broad NIR absorption consistent with high olivine abundances. Rocks observed on the lower West Spur, at the Cumberland Ridge locale, at the Husband Hill summit, and at the Haskin Ridge locale had deep 904 nm band depths and steep 754–864 nm slopes consistent with greater pyroxene abundances. These observations are consistent with results on iron-bearing mineralogy from Spirit’s Mo¨ssbauer spectrometer. Comparisons of these rock spectral classes with a set of terrestrial analog samples found similarities between the West Spur and Watchtower classes and red hematite-bearing impact melts. Fewer similarities were found in comparisons of the Columbia Hills classes with basaltic hydrovolcanic tephras

    Availability, healthiness, and price of packaged and unpackaged foods in India: A cross-sectional study

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    Background: Vulnerable populations are the most prone to diet-related disease. The availability, healthiness, and price of foods have established associations with diet-related disease in communities. However, data describing this in India are sparse, particularly in urban slums and rural areas. Aim: To quantify and compare availability, healthiness, and price of packaged and unpackaged foods and beverages in India, and to identify opportunities to improve diets and health of vulnerable populations. Methods: Nutrition data and price were collected on foods and beverages available at 44 stores in urban, urban slum, and rural areas in four states in India between May and August 2018. Healthiness was assessed using the Australasian Health Star Rating system and product retail prices were examined. Comparisons in the findings were made across state, community area type, and adherence to current and draft Indian food labeling regulations. Results: Packaged foods and beverages (n = 1443, 89%) were more prevalent than unpackaged (n = 172, 11%). Unpackaged products were healthier than packaged (mean Health Star Rating = 3.5 vs 2.0; p < 0.001) and lower in price (median price per 100 g/ml: 13.42 Indian rupees vs 25.70 Indian rupees; p < 0.001), a pattern observed across most community area types and states. 96% of packaged products were compliant with current Indian labeling regulations but only 23% were compliant with proposed labeling regulations. Conclusions: Unpackaged products were on average much healthier and lower in price than packaged foods and beverages. Food policies that support greater availability, accessibility and consumption of unpackaged foods, while limiting consumption of packaged foods, have enormous potential for sustaining the health of the Indian population

    Abundance recovery error analysis using simulated AVIRIS data

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    Measurement noise and imperfect atmospheric correction translate directly into errors in the determination of the surficial abundance of materials from imaging spectrometer data. The effects of errors on abundance recovery were investigated previously using Monte Carlo simulation methods by Sabol et. al. The drawback of the Monte Carlo approach is that thousands of trials are needed to develop good statistics on the probable error in abundance recovery. This computational burden invariably limits the number of scenarios of interest that can practically be investigated. A more efficient approach is based on covariance analysis. The covariance analysis approach expresses errors in abundance as a function of noise in the spectral measurements and provides a closed form result eliminating the need for multiple trials. Monte Carlo simulation and covariance analysis are used to predict confidence limits for abundance recovery for a scenario which is modeled as being derived from Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

    Constraining the Origin of Basaltic Volcanic Rocks Observed by Opportunity Along the Rim of Endeavour Crater

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    The Mars Exploration Rover (MER) Opportunity continues its exploration along the rim of Endeavour Crater. While the primary focus for investigation has been to seek evidence of aqueous alteration, Opportunity has observed a variety of rock types, including some that are hard and relatively unaltered. These rocks tend to occur most commonly as "float rocks" or "erratics" where the geologic setting does not clearly reveal their origin. Along the rim of Endeavour crater (Fig. 1), such rocks, commonly noted in Panoramic Camera (Pancam) left eye composites as "blue rocks", are abundant components of some of the Endeavour crater rim deposits, scree slopes, and colluvium deposits. In this abstract, we examine the similarity of several of these rocks analyzed using Opportunity's Alpha Particle X-Ray Spectrometer (APXS), images and color from the Pancam, and textures observed with the Microscopic Imager (MI. At issue is the blue rocks origin; are they impact melt or volcanic, what is their age relative to Endeavour crater, and how they are related to each other

    Spectroscopic examinations of hydro- and glaciovolcanic basaltic tuffs: Modes of alteration and relevance for Mars

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    Hydro- and glaciovolcanism are processes that have taken place on both Earth and Mars. The amount of materials produced by these processes that are present in the martian surface layer is unknown, but may be substantial. We have used Mars rover analogue analysis techniques to examine altered tuff samples collected from multiple hydrovolcanic features, tuff rings and tuff cones, in the American west and from glaciovolcanic hyaloclastite ridges in Washington state and in Iceland. Analysis methods include VNIR-SWIR reflectance, MWIR thermal emissivity, thin section petrography, XRD, XRF, and Mössbauer spectroscopy. We distinguish three main types of tuff that differ prominently in petrography and VNIR-SWIR reflectance: minimally altered sideromelane tuff, gray to brown colored smectite-bearing tuff, and highly palagonitized tuff. Differences are also observed between the tuffs associated with hydrovolcanic tuff rings and tuff cones and those forming glaciovolcanic hyaloclastite ridges. For the locations sampled, hydrovolcanic palagonite tuffs are more smectite and zeolite rich while the palagonitized hyaloclastites from the sampled sites are largely devoid of zeolites and relatively lacking in smectites as well. The gray to brown colored tuffs are only observed in the hydrovolcanic deposits and appear to represent a distinct alteration pathway, with formation of smectites without associated palagonite formation. This is attributed to lower temperatures and possibly longer time scale alteration. Altered hydro- or glaciovolcanic materials might be recognized on the surface of Mars with rover-based instrumentation based on the results of this study

    Behavioural activation written self-help to improve mood, wellbeing and quality of life in people with dementia supported by informal carers (PROMOTE): study protocol for a single-arm feasibility study.

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    Background: Increases in life expectancy have resulted in a global rise in dementia prevalence. Dementia is associated with poor wellbeing, low quality of life and increased incidence of mental health difficulties such as, low mood or depression. However, currently there is limited access to evidence-based psychological interventions for people with dementia experiencing low mood and poor wellbeing. Behavioural activation-based self-help, supported by informal carers and guided by mental health professionals, may represent an effective and acceptable solution. Methods/design: The present study is a Phase II (feasibility) single-arm trial informed by the MRC Complex Interventions Research Methods Framework. Up to fifty dementia participant/informal carer dyads will be recruited from a variety of settings including primary care, dementia-specific health settings, and community outreach. People living with dementia will receive behavioural activation based self-help and be supported by their informal carer who has received training in the skills required to support the self-help approach. In turn, during the use of the intervention the informal carer will be guided by mental health professionals to help them work through the materials and problem solve any difficulties. Consistent with the objectives of feasibility studies, outcomes relating to recruitment from different settings, employment of different recruitment methods, attrition, data collection procedures, clinical delivery and acceptability of the intervention will be examined. Clinical outcomes for people with dementia (symptoms of depression and quality of life) and informal carers (symptoms of depression and anxiety, carer burden and quality of life) will be measured pretreatment and at 3 months post-treatment allocation. Discussion: This study will examine the feasibility and acceptability of a novel behavioural activation-based self-help intervention designed to promote wellbeing and improve low mood in people living with dementia, alongside methodological and procedural uncertainties associated with research-related procedures. As determined by pre-specified progression criteria, if research procedures and the new intervention demonstrate feasibility and acceptability, results will then be used to inform the design of a pilot randomised controlled trial (RCT) to specifically examine remaining methodological uncertainties associated with recruitment into a randomised controlled design.This study is collaboratively funded by Cornwall Foundation Partnership Trust, South West Peninsula Academic Health Sciences Network and the University of Exeter

    Fracture-fill calcite as a record of microbial methanogenesis and fluid migration: a case study from the Devonian Antrim Shale, Michigan Basin

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    The Devonian Antrim Shale is an organic-rich, naturally fractured black shale in the Michigan Basin that serves as both a source and reservoir for natural gas. A well-developed network of major, through-going vertical fractures controls reservoir-scale permeability in the Antrim Shale. Many fractures are open, but some are partially sealed by calcite cements that retain isotopic evidence of widespread microbial methanogenesis. Fracture filling calcite displays an unusually broad spectrum of δ 13 C values (+34 to −41‰ PDB), suggesting that both aerobic and anaerobic bacterial processes were active in the reservoir. Calcites with high δ 13 C values (>+15‰) record cementation of fractures from dissolved inorganic carbon (DIC) generated during bacterial methanogenesis. Calcites with low δ 13 C values (<−32‰) are solely associated with outcrop samples and record methane oxidation during cement precipitation. Fracture-fill calcite with δ 13 C values between −10 and −30‰ can be attributed to variable organic matter oxidation pathways, methane oxidation, and carbonate rock buffering. Identification of 13 C-rich calcite provides unambiguous evidence of biogenic methane generation and may be used to identify gas deposits in other sedimentary basins. It is likely that repeated glacial advances and retreats exposed the Antrim Shale at the basin margin, enhanced meteoric recharge into the shallow part of the fractured reservoir, and initiated multiple episodes of bacterial methanogenesis and methanotrophic activity that were recorded in fracture-fill cements. The δ 18 O values in both formation waters and calcite cements increase with depth in the basin (−12 to −4‰ SMOW, and +21 to +27‰ PDB, respectively). Most fracture-fill cements from outcrop samples have δ 13 C values between −41 and −15‰ PDB. In contrast, most cement in cores have δ 13 C values between +15 and +34‰ PDB. Radiocarbon and 230 Th dating of fracture-fill calcite indicates that the calcite formed between 33 and 390 ka, well within the Pleistocene Epoch.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75720/1/j.1468-8123.2002.00036.x.pd
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